GraphiQL offline

[kantum]

Is your feature request related to a problem? Please describe.

GraphiQL is getting its js, css and fonts from unpkg servers, as I'm using graphql-mesh on premise for a client with no internet connexion I cannot access the UI 😿.

Describe the solution you'd like

An option in .meshrc to activate offline playground

serve:
  playground:
    offline: true

Describe alternatives you've considered

There is a yoga plugin which does that https://the-guild.dev/graphql/yoga-server/v2/features/graphiql#offline-usage but I didn't manage to install it on top of graphql-mesh.

Additional context